This book has three key aims: first, to show how the legal treatment of
cohabiting couples has changed over the past four centuries, from
punishment as fornicators in the seventeenth century to eventual
acceptance as family in the late twentieth; second, to chart how the
language used to refer to cohabitation has changed over time and how
different terms influenced policy debates and public perceptions; and,
third, to estimate the extent of cohabitation in earlier centuries. To
achieve this it draws on hundreds of reported and unreported cases as
well as legislation, policy papers and debates in Parliament; thousands
of newspaper reports and magazine articles; and innovative cohort
studies that provide new and more reliable evidence as to the incidence
(or rather the rarity) of cohabitation in eighteenth- and
nineteenth-century England. It concludes with a consideration of the
relationship between legal regulation and social trends.

Here's a peak at the TOC:

1. Introduction
2. Fornicators: the punishment of illicit sex
3. No name: law, morality and precedent
4. Unmarried wives in war and peace
5. Living in sin: concerns and changes
6. 'Stable illicit unions': cohabitation and the reform of divorce law
7. Common-law wives: the 1970s and the creation of a myth
8. Live-in lovers: trying to get back to basics
9. Partners: New Labour and neutrality
10. Conclusion